This invention relates to a vehicle frame and more particularly to an improved front frame subassembly for a snowmobile.
In snowmobiles and particularly the larger versions of snowmobiles, the frame assembly is generally comprised of two main frame subassemblies. The first is a comprised primarily of generally inverted U-shaped sheet metal member that supports the seat of the snowmobile on its upper surface and which encloses and overlies the drive belt. A front frame subassembly is generally made up of a pair of side plates that are reinforced by a plurality of box-shaped cross members that extend between the side plates. The engine, the front skis and steering mechanism are all carried by this front frame assembly.
Because of the construction, it is necessary to locate the cross members in such a way that they are either detachable or will clear the engine and other components supported thereby. This frequently results in sacrifices in strength and rigidity.
More importantly, however, the aforenoted type of front frame subassembly requires considerable manual labor for fabrication and assembly. A wide variety of welds or rivets or other fasteners are required to secure all of the components together, some of which must be detachable for service purposes.
In addition to the aforenoted problems in connection with frame constructions, the front frame assembly generally is disposed forwardly of the drive belt of the snowmobile, as has been noted. This presents a problem in conjunction with the positioning and supporting of additional components or auxiliary for the engine such as its heat exchangers or radiators. The radiator should be mounted in an area where it can receive adequate airflow but also should be mounted in such a way so as to avoid damage.
It is, therefore, a principal object of this invention to provide an improved frame subassembly for the front of a vehicle such as a snowmobile that has high rigidity, low-cost and which affords a convenient mounting for a radiator and wherein the airflow path across the radiator is substantially unobstructed.
It is a further object of this invention to provide an improved front frame subassembly for a snowmobile wherein the frame subassembly not only mounts but is reinforced by a heat exchanger for the engine cooling system.